The present application relates to electric or battery-operated hair cutting appliances such as hair clippers, hair trimmers, and more particularly, to a bladeset for such devices.
Electric and battery-operated hair clippers are well known to hair styling professionals and laymen alike, and generally include a bladeset having a moving blade reciprocating with respect to a stationary blade. Typically, each blade has a row of teeth projecting from an edge along a width of the blade such that the opposing rows of the moving and stationary blades are arranged substantially parallel to and in contact with each other. While variations in blade tooth configuration are known, in some conventional hair clippers, the teeth on each blade extend approximately the same distance from their respective blades, such that the tips of the teeth generally define a straight line. Generally, V-shaped cavities are formed between adjacent blade teeth for receiving the hair to be cut.
During operation, a user or stylist moves the clipper through a customer's hair. As the clipper travels through the hair, hair strands enter spaces between the stationary blade teeth. As the moving blade reciprocates relative to the stationary blade, the hair strands are cut by the scissors action created between cutting edges of the moving and stationary blade teeth. An area of overlap between the stationary blade teeth and the moving blade teeth created during reciprocation is known in the art as the cutting zone.
The amount of hair that can enter the cutting zone is dependant in part upon the speed at which the clipper is moved through the hair. Accordingly, when the user moves the clipper through the hair at a slow rate, a relatively small amount of hair enters the cutting zone and can generally be cut by the blade teeth. However, when the user rapidly moves the clipper through the hair to be cut, the hair strands penetrate deeper into the cutting zone, allowing more strands to enter the cutting zone and requiring more strands to be cut in each reciprocating cycle. In current hair clippers, a common side effect of such rapid movement is that the bladeset becomes overloaded with hair, which can cause the blades to stall, separate or fail to properly cut the hair.
Hair clippers having a moving blade including long and short teeth alternately arranged along the blade have been developed but are typically not known to reduce these overload effects. Specifically, in the hair clipper in U.S. Pat. No. 2,641,833 to Need, a staggered tooth design is configured such that the long teeth cut half of the hair that enters the blade cavities, and the short teeth cut the remaining half, producing a two-tiered or feathered cut. Although the staggered tooth design in Need distributes the cutting load between the long and short teeth, the number of cuts per reciprocation of the moving blade is not changed, and accordingly, during increased clipper feed rates, hair can still overload or become caught in the blade cavities.
Accordingly, there is a need for an improved bladeset for a hair clipper that provides enhanced cutting performance at increased feed rates, as occurs when a clipper is moved relatively rapidly through the hair. There is a further need for an improved hair clipper bladeset that reduces the overload effects caused by such increased feed rates.